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Open access

D Santi, A R M Granata, and M Simoni

Introduction

The aim of this study is to comprehensively evaluate whether FSH administration to the male partner of infertile couples improves pregnancy rate, spontaneously and/or after assisted reproductive techniques (ART).

Methods

Meta-analysis of controlled clinical trials in which FSH was administered for male idiopathic infertility, compared with placebo or no treatment. Randomization was not considered as an inclusion criterion.

Results

We found 15 controlled clinical studies (614 men treated with FSH and 661 treated with placebo or untreated). Concerning the type of FSH, eight studies used recombinant FSH, whereas seven studies used purified FSH. Nine studies evaluated spontaneous pregnancy rate, resulting in an overall odds ratio (OR) of about 4.5 (CI: 2.17–9.33). Eight studies evaluated pregnancy rate after ART, showing a significant OR of 1.60 (CI: 1.08–2.37). Sub-dividing studies according to the FSH preparations (purified/recombinant), pregnancy rate improvement remained significant for each preparation. Eleven studies considered sperm quality after FSH treatment, finding a significant improvement of sperm concentration (2.66×106/ml, CI: 0.47–4.84), but not of concentration of sperm with progressive motility (1.22×106/ml, CI: −0.07 to 2.52). Three trials evaluated testicular volume, showing a non-significant increase in men treated (1.35 ml, CI: −0.44 to 3.14).

Conclusion

The results of controlled clinical trials available in the literature indicate an improvement of pregnancy rate after FSH administration to the male partner of infertile couples, both spontaneously and after ART. However, the heterogeneity of studies, the high risk of bias and the lack of precise criteria to guide FSH administration limit the strength of these results. Future studies should be designed to identify the markers of FSH response which are helpful in the decision-making process. Meanwhile, the use of FSH in the treatment of male infertility should be cautious.

Open access

Jan-Bernd Stukenborg, Kirsi Jahnukainen, Marsida Hutka, and Rod T Mitchell

Testicular function and future fertility may be affected by cancer treatment during childhood. Whilst survival of the germ (stem) cells is critical for ensuring the potential for fertility in these patients, the somatic cell populations also play a crucial role in providing a suitable environment to support germ cell maintenance and subsequent development. Regulation of the spermatogonial germ-stem cell niche involves many signalling pathways with hormonal influence from the hypothalamo-pituitary-gonadal axis. In this review, we describe the somatic cell populations that comprise the testicular germ-stem cell niche in humans and how they may be affected by cancer treatment during childhood. We also discuss the experimental models that may be utilized to manipulate the somatic environment and report the results of studies that investigate the potential role of somatic cells in the protection of the germ cells in the testis from cancer treatment.

Open access

Jens F Rehfeld

The birth certificate for endocrinology was Bayliss’ and Starling’s demonstration in 1902 that regulation of bodily functions is not only neuronal but also due to blood-borne messengers. Starling named these messengers hormones. Since then transport via blood has defined hormones. This definition, however, may be too narrow. Thus, today we know that several peptide hormones are not only produced and released to blood from endocrine cells but also released from neurons, myocytes, immune cells, endothelial cells, spermatogenic cells, fat cells, etc. And they are often secreted in cell-specific molecular forms with more or less different spectra of activity. The present review depicts this development with the story about cholecystokinin which was discovered in 1928 as a hormone and still in 1976 was conceived as a single blood-borne peptide. Today’s multifaceted picture of cholecystokinin suggests that time may be ripe for expansion of the hormone concept to all messenger molecules, which activate their target cells – irrespective of their road to the target (endocrine, neurocrine, neuronal, paracrine, autocrine, etc.) and irrespective of their kind of activity as classical hormone, growth factor, neurotransmitter, adipokine, cytokine, myokine, or fertility factor.

Open access

A Rehfeld, D L Egeberg, K Almstrup, J H Petersen, S Dissing, and N E Skakkebæk

Human sperm cell function must be precisely regulated to achieve natural fertilization. Progesterone released by the cumulus cells surrounding the egg induces a Ca2+ influx into human sperm cells via the CatSper Ca2+-channel and thereby controls sperm function. Multiple chemical UV filters have been shown to induce a Ca2+ influx through CatSper, thus mimicking the effect of progesterone on Ca2+ signaling. We hypothesized that these UV filters could also mimic the effect of progesterone on sperm function. We examined 29 UV filters allowed in sunscreens in the US and/or EU for their ability to affect acrosome reaction, penetration, hyperactivation and viability in human sperm cells. We found that, similar to progesterone, the UV filters 4-MBC, 3-BC, Meradimate, Octisalate, BCSA, HMS and OD-PABA induced acrosome reaction and 3-BC increased sperm penetration into a viscous medium. The capacity of the UV filters to induce acrosome reaction and increase sperm penetration was positively associated with the ability of the UV filters to induce a Ca2+ influx. None of the UV filters induced significant changes in the proportion of hyperactivated cells. In conclusion, chemical UV filters that mimic the effect of progesterone on Ca2+ signaling in human sperm cells can similarly mimic the effect of progesterone on acrosome reaction and sperm penetration. Human exposure to these chemical UV filters may impair fertility by interfering with sperm function, e.g. through induction of premature acrosome reaction. Further studies are needed to confirm the results in vivo.

Open access

Teodoro Durá-Travé, Fidel Gallinas-Victoriano, María Malumbres-Chacon, Lotfi Ahmed-Mohamed, María Jesús Chueca -Guindulain, and Sara Berrade-Zubiri

Objective

The objective of this study was to analyze whether some auxological characteristics or a single basal gonadotropin measurement will be sufficient to distinguish the prepubertal from pubertal status.

Methods

Auxologycal characteristics were recorded and serum LH and FSH were measured by immunochemiluminescence assays before and after GnRH stimulation test in a sample of 241 Caucasian girls with breast budding between 6- and 8-years old. Peak LH levels higher than 5 IU/L were considered a pubertal response. Area under the curve, cut-off points, sensitivity, and specificity for auxologycal variables and basal gonadotropins levels were determined by receiver operating curves.

Results

There were no significant differences in age at onset, weight, height, BMI and height velocity between both groups. Bone age was significantly higher in pubertal girls (P < 0.05), although with limited discriminatory capacity. The sensitivity and specificity for the basal LH levels were 89 and 82%, respectively, for a cut off point of 0.1 IU/L. All girls in the pubertal group had a basal LH higher than 1.0 IU/L (positive predictive value of 100%). There was a wide overlap of basal FSH and LH/FSH ratio between prepubertal and pubertal girls.

Conclusions

Auxologycal characteristics should not be used only in the differential diagnosis between prepubertal from pubertal status in 6- to 8-year-old girls. We found a high specificity of a single basal LH sample and it would be useful for establishing the diagnosis of puberty in this age group, reducing the need for GnRH stimulation testing.

Open access

Mei Li, Yanfei Chen, Binrong Liao, Jing Tang, Jingzi Zhong, and Dan Lan

Objective

To evaluate the characteristics and significance of serum kisspeptin and makorin ring finger protein 3 (MKRN3) levels for the diagnosis of central precocious puberty (CPP) in girls.

Method

Thirty four individuals with CPP, 17 individuals with premature thelarche (PT), and 28 age-matched prepubertal girls as normal control (NC) were recruited in this case–control study. Physical measurements included BMI and tests for breast, bone, and sexual characteristics. Biochemical measurements included serum LH, FSH, estradiol, insulin-like growth factor-1, MKRN3, and kisspeptin. Blood samples were taken from individuals with CPP and PT before the gonadotrophin-releasing hormone stimulation test and at 30, 60, 90, and 120 min after injection with triptorelin.

Results

Serum kisspeptin levels were higher in the CPP group when compared to the NC group (P = 0.020), while serum MKRN3 levels were lower in the two groups (P = 0.028). There were no significant differences between the CPP and PT groups as well as the PT and NC groups (all, P > 0.05). The cut-off value of serum kisspeptin differentiating patients with CPP from those without CPP was 0.40 nmol/L, with 82.4% sensitivity and 57.1% specificity, while the cut-off value of serum MKRN3 was 0.33 pmol/L, with 79.4% sensitivity and 53.6% specificity. The area under the curves (AUCs) of both kisspeptin and MKRN3 for differentiating those girls with CPP from PT were less than 0.5.

Conclusions

Serum levels of kisspeptin and MKRN3 may play an auxiliary role in predicting CPP. However, the two measurements were not able to differentiate girls with CPP from PT and prepubertal control. This study emphasizes the need to search for markers to simplify the accurate diagnosis of CPP in girls.

Open access

Imane Benabbad, Myriam Rosilio, Maité Tauber, Emmanuel Paris, Anne Paulsen, Lovisa Berggren, Hiren Patel, Jean-Claude Carel, and the Phoenix Study Group

Objective

There is a scarcity of data from randomised controlled trials on the association of growth hormone (GH) with gonadotrophin-releasing hormone agonists in idiopathic short stature (ISS), although this off-label use is common. We aimed to test whether delaying pubertal progression could increase near-adult height (NAH) in GH-treated patients with ISS.

Methods

Patients with ISS at puberty onset were randomised to GH with leuprorelin (combination, n = 46) or GH alone (n = 45). NAH standard deviation score (SDS) was the primary outcome measure. The French regulatory authority requested premature discontinuation of study treatments after approximately 2.4 years; patients from France were followed for safety.

Results

Mean (s.d.) baseline height SDS was −2.5 (0.5) in both groups, increasing at 2 years to −2.3 (0.6) with combination and −1.8 (0.7) with GH alone. NAH SDS was −1.8 (0.5) with combination (n = 19) and −1.9 (0.8) with GH alone (n = 16). Treatment-emergent adverse events and bone fractures occurred more frequently with combination than GH alone.

Conclusion

Due to premature discontinuation of treatments, statistical comparison of NAH SDS between the two cohorts was not possible. During the first 2–3 years of treatment, patients treated with the combination grew more slowly than those receiving GH alone. However, mean NAH SDS was similar in the two groups. No new GH-related safety concerns were revealed. A potentially deleterious effect of combined treatment on bone fracture incidence was identified.

Open access

M Axelstad, U Hass, M Scholze, S Christiansen, A Kortenkamp, and J Boberg

Human semen quality is declining in many parts of the world, but the causes are ill defined. In rodents, impaired sperm production can be seen with early life exposure to certain endocrine-disrupting chemicals, but the effects of combined exposures are not properly investigated. In this study, we examined the effects of early exposure to the painkiller paracetamol and mixtures of human relevant endocrine-disrupting chemicals in rats. One mixture contained four estrogenic compounds; another contained eight anti-androgenic environmental chemicals and a third mixture contained estrogens, anti-androgens and paracetamol. All exposures were administered by oral gavage to time-mated Wistar dams rats (n = 16–20) throughout gestation and lactation. In the postnatal period, testicular histology was affected by the total mixture, and at the end of weaning, male testis weights were significantly increased by paracetamol and the high doses of the total and the anti-androgenic mixture, compared to controls. In all dose groups, epididymal sperm counts were reduced several months after end of exposure, i.e. at 10 months of age. Interestingly, the same pattern of effects was seen for paracetamol as for mixtures with diverse modes of action. Reduced sperm count was seen at a dose level reflecting human therapeutic exposure to paracetamol. Environmental chemical mixtures affected sperm count at the lowest mixture dose indicating an insufficient margin of safety for the most exposed humans. This causes concern for exposure of pregnant women to paracetamol as well as environmental endocrine disrupters.

Open access

J Brossaud, V Pallet, and J-B Corcuff

Vitamin A (retinol) is a micronutrient critical for cell proliferation and differentiation. In adults, vitamin A and metabolites such as retinoic acid (RA) play major roles in vision, immune and brain functions and tissue remodelling and metabolism. This review presents the physiological interactions of retinoids and endocrine tissues and hormonal systems. Two endocrine systems have been particularly studied. In the pituitary, retinoids target the corticotrophs with a possible therapeutic use in corticotropinomas. In the thyroid, retinoids interfere with iodine metabolism and vitamin A deficiency aggravates thyroid dysfunction caused by iodine-deficient diets. Retinoids use in thyroid cancer appears less promising than expected. Recent and still controversial studies investigated the relations between retinoids and metabolic syndrome. Indeed, retinoids contribute to pancreatic development and modify fat and glucose metabolism. However, more detailed studies are needed before planning any therapeutic use. Finally, retinoids probably play more minor roles in adrenal and gonads development and function apart from their major effects on spermatogenesis.

Open access

Elena Galazzi, Paolo Duminuco, Mirella Moro, Fabiana Guizzardi, Nicoletta Marazzi, Alessandro Sartorio, Sabrina Avignone, Marco Bonomi, Luca Persani, and Maria Teresa Bonati

Ulnar-mammary syndrome (UMS) is characterized by ulnar defects, and nipple or apocrine gland hypoplasia, caused by TBX3 haploinsufficiency. Signs of hypogonadism were repeatedly reported, but the mechanisms remain elusive. We aim to assess the origin of hypogonadism in two families with UMS. UMS was suspected in two unrelated probands referred to an academic center with delayed puberty because of the evident ulnar ray and breast defects in their parents. Clinical, biochemical and genetic investigations proved the existence of congenital normosmic IHH (nIHH) associated with pituitary hypoplasia in the two probands who were heterozygous for novel TBX3 pathogenic variants. The mutations co-segregated with delayed puberty, midline defects (nose, teeth and tongue anomalies) and other variable features of UMS in the two families (absent axillary hairs and nipple hypoplasia, asymmetrical features including unilateral ulnar or renal abnormalities). The combined analysis of these findings and of the previous UMS reports showed delayed puberty and other signs of hypogonadism in 79 and 37% of UMS males, respectively. Proband 1 was followed up to adulthood with persistence of nIHH. In conclusion, UMS should be suspected in patients with delayed puberty and midline defects, including pituitary hypoplasia, in the presence of mild cues for TBX3 mutation, even in the absence of limb malformations. In addition, TBX3 should be included among candidate genes for congenital nIHH.